Resilient cap for the keys of typewriters or similar machines



June 9, 192's. 1,541,043

R. S. GRAHAM RESILIENT CAP FOR THE KEYS OF TYPEWRITERS OR SIMILAR MAGHINES Filed Feb. 6. 1924 ATTORNEY.

Patented June 9, 1925.

nn rsn STATES FLL1VIER,-0F W YORK; Y.

RESILIENT CA]? ronrnn eys or rrrrnwnr'rnns on srmrrlnn MAenrN-ns.

Application area February 6, i924. Serial an. v690,899.

To all whom it may concern;

Be it known that I, Rosana S. GR A a citizen of the United States, residing in the city, county, andState of New York, have invented certain new and useful 11nprovements in a Resilient :Gap for the Keys of Typewriters or Similar Machines, of whichthe following is a full, clear, and exact description, such ,as will enable others skilled in the art to which it appertains to make and use the same. I

This invention relates to a resilient cap for the keys of typewriters, or similar ngiachines, and the objects (rt-the inuentiou are to provide a resilient or cushion-ed cap ithat is interchangeable without reference to the index letteror numeral of the key to which it is .to be applied. Further object-s ofthe invention are to provide a cap, that will, when applied to a key, have a dish shaped v top provided with cushion nen-ibers that are spaced away from the top of the key to pen mit \of the cushion members being flexed to provide a cushioning effect to the linger of the operator. Still further objects of the invention are to provide means for guiding or stretching the cap over the .top .of a key, which will :perniitof its easy removal.

Referring to the drawings:

Figure *1 is a perspectiue view of the key end of a key bar of a typewriteror similar machine provided with a resilient ,cap made in accordance with theinvention.

Figure 2 is a top View of Figure '1.

Figure 3 is a sectional view on the line 3-3 of Figure 2.

Figure 4 is a sectional view of the resilient cap on the line 4-4 of Figure 5.

Figure 5 is a bottom view of the resilient cap. 1 i

In the drawings 1 designates the key end of an ordinary typewriter key bar, or the key end of any similar machine, which is provided in the present instance with the usual key comprising, a circular disk 2 having on its upper surface an index letter or numeral, the same being covered with a circular disk 3 of glass both supported on a metal key base 4 having an upturned edge 5 and a shank 6 secured to the upturned portion of the key bar. The disks 2 and 3 are held in position on the top of the key base 4 by means of a circular flange? surrounding the outer edge of the upturned edge 5 and crimped over the top thereof,

and the circumferential edges of the disks 2 and 3, so as to provlde a circular beaded edge 8; a

li he {beaded edge 8 of the circular flange 7 'forms a continuousbead or ridge about the upper surface of the key not only :to

7 tion.

The typewriter key cap 9 is, in accordance with the present invention, preferably made of rubber suitably low disk shaped cap comprising a cylius d-rical body 10, the innerdiameter od'rwj hich is less than the outer diaineter of the key,

'tliejkey' ca p being open at :lEllO bottom and provided with an inner guide flange ill :tllfi inner edge of which is cut to ilziare outward. as shown at 12 to facilitate the key ca p being forced over the ;top of the *key utter which the guide vflange 11 as sunesnormal l oclretl position a ainst-the bottom .of :the

'ur i ia The key cap 9 is alsoyin accordance with the present invention, provided with a fiat top having side and end cushion members 13 and 14, which surround a top opening so as to make visible the index letter or numeral on the disk 2. In the present instance the top opening in key cap 9 is made greater in length than in breadth, the greater length being in the direction of the key bar to more easily show the index letter or numeral, although if desired the top opening can be made round or other convenient shape to expose the index letter or numeral, however, the elongated opening as shown in the drawings is to be preferred. a

The side and end cushion members 13 and 14 are preferably made of uniform thickness and preferably thicker than the sides of the cylindrical body portion 10.

A key cap made as above described will, when forced over the top of a key, as before described, act by reason of the raised beaded moldedto provide a hol- 1,541,045 rgrsn'r crimes.

aoeER-r s- GRAHAM, or ne ton; YQ, an enna r arsen ls so were secure the parts of the key together but also I to provide .asi-utabrle work-mg surface for edge 8v on thecircumference ofthe key to become dish shaped as shown in Figures 1 and 3 without however, the bottom of the inner edges of the side and end cushion members 13 and 14 coming in contact with the upper surface of the key as clearly shown in Figure 3.

. Thedish shape of the top of the key cap is caused not only by the fact that the inner edges of the side and end cushion members are unsupported, but to the fact that the inner circumference of the body portion is less than the outer circumference of'the key, which acts to stretch the top of the key cap taut and in so doing dish the same at the center which it is permitted todo by reason of the raised beaded edge 8 on the key and the shape of the opening in the key cap.

It will be seen therefore that a cap provided with an elongated opening, similar to that shown in the drawing, which provides relatively broad side cushion members as compared with relatively narrow end cushion members, will function better as a cash ion, and have a greater cushion effect than if, for example, the opening was round in which event the unsupported area would be less.

From the above description it will be seen that a resilient cap is provided which by reason of its construction can easily be forced over, or removed from, the top of a key for a typewriter or similar machine, and that the same will in view of its construction provide a disk shaped top, or working surface, that is spaced away from the top surface of the'key and which will permit of the same being flexed by the finger of the operator to cushion the blow when struck.

While the invention has been described with particular reference to the details of construction the same is not to be considered as limited thereto as many changes can be made and still fall within the scope of the invention set fol-thin the following claims.

What I claim is: v p I 1. A cap for typewriter and similar keys provided with an upwardly extending circumferential ridge, said cap beingmade in the form of a hollow disk of slightly smaller 7 diameter than the key, a guide flange sccured to the bottom of said cap to facilitate the same being stretchedxover said key, the top of said cap being provided with side and end cushion members, said side members being broader than said end members, and an opening in the top of said cap surrounded by said cushion members, the top of said cap being arranged to rest upon the ridge portion of said key, the central portion'of the top of said cap being spaced away from the top of the central portion of said key.

2. A cap for typewriter and similar keys provided with an upwardly extending circumferential ridge, said cap being made in the form of a hollow disk of slightly smaller diameter than the key, the top of said cap being provided with side and end cushion members said side members being broader than said end members, and an opening in the top of said cap surrounded by said cushion members, the top of said cap being normally flat but arranged to become dish shaped when forced over the top of said key into engagement with said ridge, the central portion of the top of said cap being spaced away from the top of the central portion of said key.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses; V 7 ROBERT S. GRAHAM. Witnesses:

Lno J. MATTY, LILIAN' E. POTTER. 

